diff --git a/calculator.py b/calculator.py
new file mode 100644
index 00000000..69f7acf0
--- /dev/null
+++ b/calculator.py
@@ -0,0 +1,45 @@
+
+
+def sumar(a, b):
+    return a + b
+
+def restar(a, b):
+    return a - b
+
+def multiplicar(a, b):
+    return a * b
+
+def dividir(a, b):
+    if b != 0:
+        return a / b
+    else:
+        return "Error: División por cero"
+
+def calculadora():
+    print("Seleccione una operación:")
+    print("1. Sumar")
+    print("2. Restar")
+    print("3. Multiplicar")
+    print("4. Dividir")
+
+    opcion = input("Ingrese el número de la operación: ")
+
+    try:
+        num1 = float(input("Ingrese el primer número: "))
+        num2 = float(input("Ingrese el segundo número: "))
+
+        if opcion == '1':
+            print("Resultado:", sumar(num1, num2))
+        elif opcion == '2':
+            print("Resultado:", restar(num1, num2))
+        elif opcion == '3':
+            print("Resultado:", multiplicar(num1, num2))
+        elif opcion == '4':
+            print("Resultado:", dividir(num1, num2))
+        else:
+            print("Opción no válida")
+    except ValueError:
+        print("Error: Entrada no válida")
+
+if __name__ == "__main__":
+    calculadora()
\ No newline at end of file
diff --git a/card_draw.py b/card_draw.py
index 4f4bf631..bc4bd7af 100644
--- a/card_draw.py
+++ b/card_draw.py
@@ -4,12 +4,12 @@
 import itertools, random
 
 # make a deck of cards
-deck = list(itertools.product(range(1,14),['Spade','Heart','Diamond','Club'])
+deck = list(itertools.product(range(1, 14), ['Spade', 'Heart', 'Diamond', 'Club']))  # Fixed missing parenthesis
 
 # shuffle the cards
 random.shuffle(deck)
 
 # draw five cards
 print("You got:")
-for i in range(5)
-   print(deck[i][0], "of", deck[i][1]
+for i in range(5):  # Fixed missing colon
+    print(deck[i][0], "of", deck[i][1])  # Fixed missing parenthesis
diff --git a/hello.py b/hello.py
new file mode 100644
index 00000000..cd69d0dd
--- /dev/null
+++ b/hello.py
@@ -0,0 +1 @@
+print("Hola Mundo")
diff --git a/sum_elements.py b/sum_elements.py
index 2731a254..d8d5de3c 100644
--- a/sum_elements.py
+++ b/sum_elements.py
@@ -1,37 +1,39 @@
-#A poorly written example of a program in Python. It prompts the user for the number of elements to sum, takes those integers as input, and handles some basic error cases
-
 MAX = 100
 
 def calculate_sum(arr):
-   result = 0
-   for num in arr:
-      result += num
-   return result
+    return sum(arr)  # Usar la función integrada sum()
+
+def get_valid_input(prompt, validation_fn):
+    while True:
+        try:
+            value = int(input(prompt))
+            if validation_fn(value):
+                return value
+            print("Invalid input. Please try again.")
+        except ValueError:
+            print("Invalid input. Please enter a valid integer.")
+
+def get_number_of_elements():
+    return get_valid_input(
+        "Enter the number of elements (1-100): ",
+        lambda x: 1 <= x <= MAX
+    )
+
+def get_elements(n):
+    arr = []
+    print(f"Enter {n} integers:")
+    for _ in range(n):
+        arr.append(get_valid_input("Enter an integer: ", lambda x: True))
+    return arr
 
 def main():
-   try:
-      n = int(input("Enter the number of elements (1-100): "))
-      if not 1 <= n <= MAX:
-            print("Invalid input. Please provide a digit ranging from 1 to 100.")
-            exit(1)
-
-      arr = []
-
-      print(f"Enter {n} integers:")
-      for _ in range(n):
-            try:
-               arr.append(int(input()))
-            except ValueError:
-               print("Invalid input. Please enter valid integers.")
-               exit(1)
-
-      total = calculate_sum(arr)
-
-      print("Sum of the numbers:", total)
-
-   except KeyboardInterrupt:
-      print("\nProgram terminated by user.")
-      exit(1)
+    try:
+        n = get_number_of_elements()
+        arr = get_elements(n)
+        print("Sum of the numbers:", calculate_sum(arr))  # Llamar directamente a calculate_sum()
+    except KeyboardInterrupt:
+        print("\nProgram terminated by user.")
+        exit(1)
 
 if __name__ == "__main__":
-   main()
+    main()
diff --git a/weather_script.py b/weather_script.py
new file mode 100644
index 00000000..1f90addb
--- /dev/null
+++ b/weather_script.py
@@ -0,0 +1,30 @@
+import requests
+
+class WeatherAPI:
+    def __init__(self, api_key):
+        self.api_key = api_key
+        self.base_url = "https://api.openweathermap.org/data/2.5/weather"
+
+    def get_weather(self, city_name, units="metric"):
+        params = {
+            "q": city_name,
+            "appid": self.api_key,
+            "units": units
+        }
+        try:
+            response = requests.get(self.base_url, params=params)
+            response.raise_for_status()
+            return response.json()
+        except requests.exceptions.RequestException as e:
+            print(f"Error fetching weather data: {e}")
+            return None
+
+# Example usage:
+# Replace 'your_api_key_here' with your OpenWeatherMap API key
+if __name__ == "__main__":
+    api_key = "your_api_key_here"
+    weather_api = WeatherAPI(api_key)
+    city = "London"
+    weather_data = weather_api.get_weather(city)
+    if weather_data:
+        print(weather_data)
\ No newline at end of file